The DM will always be narrating more than the players. But, players having minor narative control doesn't suddenly make them non-role players.
An example from my game only today:
One of the players has a rifle with the Thunderburst property - once per day, his next shot becomes a Burst 1 centred on the target.
He was up in the rigging when pirates boarded their ship. There were three of the generic pirates clumped around the leader of the boarding party, 'Big Axe' Van Helt.
"I lean out from my perch in the rigging," the player said, "and fire my rifle at the small keg of gunpowder one of the crew left out on the deck, now sitting near Big Axe's boot."
And he spent his Daily item power to create the Burst 1.
As DM, had I specified a keg of gunpowder? Absolutely not. If he'd tried the same trick
without a Thunderburst rifle? I might have allowed something from p42 if he pulled off a skill check first... maybe. But defining the cinematics to describe the mechanics he already had written down on his character sheet? Hell, yeah! I'm more than happy to let him 'remind' me about the keg one of my NPCs left lying around!
Now, did he role-play long enough to lean out of the rigging, stop role-playing, narrate the existence of the gunpowder, then resume roe-playing in order to shoot it?
Bollocks to that, I say. He was role-playing while his character shot a keg of gunpowder.
-Hyp.